Sounding the Tsunami Alarm

The National Oceanic Atmospheric Administration (NOAA) has put the final touches on a system designed to alert U.S. territories when a tsunami strike is imminent.

The system was initiated shortly after a devastating tsunami killed more than 300,000 Indonesians on Dec. 26, 2004. The gargantuan wave was caused by an earthquake in the Indian Ocean. Because the Pacific and Indian Oceans have a high percentage of convergent faults, tsunami occurrences are more common, with more than 80 percent of all tsunamis taking place in that region. The Pacific Ocean region alone accounts for three out of four tsunamis.

The NOAA warning system consists of 39 buoys called deep-ocean assessment and reporting stations (DARTs). They consist of a bottom pressure sensor anchored to the seafloor and a companion moored surface buoy. The NOAA said that an acoustic link transmits data from the bottom pressure sensor to the surface buoy, and then satellite links relay the data to NOAA tsunami warning centers. The tsunami warning system in turn provides alerts to coastal communities not only in the Pacific, but also the Atlantic, Caribbean, and the Gulf of Mexico. The NOAA said that DARTs are now positioned in every seismic zone that could generate a tsunami that would affect the U.S.

“Completing the U.S. tsunami warning system is truly a monumental triumph that includes the advancement of the science, development, and testing of cutting-edge technology, and the large scale project management skills that brought it all together on a global scale,” said retired Navy Vice Adm. and NOAA Administrator Conrad C. Lautenbacher, in a release. “As a young scientist who researched tsunamis and built early models of their effects, I never imagined that we could come so far in our ability to understand, detect, model, and warn on such a scale as we have just achieved.”